1. Field of the Invention
The present invention generally relates to suspension systems for bicycles and, more particularly, is concerned with an electronically controlled bicycle suspension apparatus for actively adjusting the bicycle suspension to adapt to the immediate conditions being experienced by the bicyclist.
2. Description of the Prior Art
In recent years suspension systems on bicycles, particularly on mountain bikes, have become more common. Some examples of bicycle suspension systems are the ones disclosed in U.S. Pat. No. 4,679,811 to Shuler, U.S. Pat. No. 4,881,750 to Hartmann, U.S. Pat. No. 5,044,648 to Knapp, U.S. Pat. Nos. 5,308,099 and 5,509,674 to Browning, U.S. Pat. Nos. 5,445,401 and 5,509,677 to Bradbury, and U.S. Pat. Nos. 5,456,480 and 5,580,075 to Turner et al.
A common drawback of most suspension systems is that they are passive mechanical systems which do not sense change in riding conditions nor automatically adjust in response thereto. This results in suspension systems that may be too stiff for extremely rocky, steep descents and too soft for riding on surfaced roads and bike paths. Some suspension systems allow the rider to adjust the pretension on the suspension components. However, this process normally requires stopping the bicycle to manually make the necessary adjustments. The rider must estimate the stiffness or softness that might be required for the anticipated riding conditions. Also, the adjustments in some of these systems require the use of tools.
The above-cited Turner et al. U.S. Pat. No. 5,456,480 contains a caution to designers that electronic control of bicycle suspensions is impractical. This statement seems intended to discourage any attempts to improve bicycle suspensions through the development of an electronically-based solution to controlling the suspensions in order to adjust to different riding conditions. Nevertheless, it is the perception of the inventor herein that a different approach, possibly one that is electronically-based, is needed in the design of suspension systems for bicycles, especially on mountain bikes, to improve their handling and performance.